Pest Information – Ticks
Ticks are ectoparasites living on the blood of mammals, birds, and occasionally reptiles and amphibians. Ticks transmit the widest variety of pathogens of any blood sucking arthropod. This site will focus on the ticks most commonly found in Hawaii. Learn about their Appearance, Habitat, Diet, Health Risks, and Reproduction.
Brown Dog Ticks
Scientific Name
Rhipicephalus sanguineus
Appearance
Adult male ticks are flat, about 1/8 inch long and uniformly red-brown with tiny pits scattered over the back. They do not enlarge upon feeding as do females. Before feeding, adult female ticks resemble the males in size, shape and color. As they feed, females become engorged and swell to 1/2 inch long and 1/4 inch wide. Frequently, people report having different types of ticks, or adults and “babies”. In fact, generally what they are seeing are engorged and unengorged ticks or different stages of development.
Habitat
The Brown Dog Tick, the most common tick, can be found in 49 states and in a variety of habitats, including shaded sandy areas, cracks and crevices in houses, garages and dog runs, and even on walls and ceilings of homes. One will often become aware of an in-house infestation when they climb walls in search of a hiding place.
Diet
Brown Dog Ticks feed on the blood of dogs and occasionally wildlife or humans.
Health Risks
In Hawaii, these ticks feed all year long and can transmit ehrlichosis, babesoiosis, and thrombocytopenia. If the infestation is severe, the various growth stages of the tick can be found sucking blood almost anywhere on the dog. Continuance of this activity will result in the pet’s loss of vitality, leading to irritability. The Brown Dog Tick has been reported to be a vector of Rocky Mountain spotted fever in the western hemisphere, boutonneuse virus in Europe, and malignant jaundice of dogs in other parts of the world.
Life Cycle
The engorged female drops off the host dog and seeks a sheltered spot in which to lay up to 5,000 tiny, dark brown eggs. The eggs hatch in 19-60 days into minute 6-legged larvae or seed ticks. They attach to a dog as soon as possible but can survive for 8 months without food or water. After engorging for 3-6 days they seek a sheltered place in which to molt. In 6-23 days they become 8-legged, reddish brown nymphs, which can survive for about 3 months without food or water. They again attach and engorge for 4-9 days, becoming oval, about 1/8″ (3 mm) wide, and dark gray. The nymphs then drop off, hide, and usually molt in 12-19 days into adults. Although the adults attach to a dog at the first opportunity, they can survive 18 months before attachment. Once attached, they engorge for 6-50 days, mate, and the females drop off to lay eggs and repeat the cycle. Hawaii’s ideal year-around weather conditions, where the cycle can occur year-round both inside houses and in outside kennels and dog runs, can result in overlapping generations and, therefore, “population explosions”.
Interesting Facts
Dogs do not become infested with Brown Dog Ticks by direct contact with other dogs. Ticks feeding on a dog drop off and molt before they will resume host-seeking behavior and attach to another dog. The home may become infested even though the dog is not kept there.